# Hydraulics And Fluid Mechanics Set 2

This set of Hydraulics and Fluid Mechanics Multiple Choice Questions & Answers (MCQs) focuses on Hydraulics And Fluid Mechanics Set 2

Q1 | An object having 10 kg mass weighs 9.81 kg on a spring balance. The value of 'g' at this place is
• 10 m/sec²
• 9.81 m/sec²
• 9.75 m/sec²
• 9 m/sec
Q2 | A flow is called hyper-sonic, if the Mach number is
• Less than unity
• Unity
• Between 1 and 6
• None of these
Q3 | Liquids
• Cannot be compressed
• Occupy definite volume
• Are not affected by change in pressure and temperature
• None of the above
Q4 | When a cylindrical vessel containing liquid is resolved, the surface of the liquid takes the shape of
• A triangle
• A paraboloid
• An ellipse
• None of these
Q5 | Fluid is a substance that
• Cannot be subjected to shear forces
• Always expands until it fills any container
• Has the same shear stress at a point regardless of its motion
• Cannot remain at rest under action of any shear force
Q6 | The force exerted by a moving fluid on an immersed body is directly proportional to the rate of change of momentum due to the presence of the body. This statement is called
• Newton's law of motion
• Newton's law of cooling
• Newton's law of viscosity
• Newton's law of resistance
Q7 | The property of a fluid which enables it to resist tensile stress is known as
• Compressibility
• Surface tension
• Cohesion
Q8 | The loss of pressure head in case of laminar flow is proportional to
• Velocity
• (Velocity)2
• (Velocity)3
• (Velocity)4
Q9 | The surface tension of mercury at normal temperature compared to that of water is
• More
• Less
• Same
• More or less depending on size of glass tube
Q10 | An air vessel is provided at the summit in a siphon to
• Avoid interruption in the flow
• Increase discharge
• Increase velocity
• Maintain pressure difference
Q11 | The unit of viscosity is
• Metres² per sec
• kg-sec/metre
• Newton-sec per metre²
• Newton-sec per meter
Q12 | Select the correct statement
• Weber's number is the ratio of inertia force to elastic force.
• Weber's number is the ratio of gravity force to surface tension force.
• Weber's number is the ratio of viscous force to pressure force.
• Weber's number is the ratio of inertia force to surface tension force.
Q13 | Choose the wrong statement. Alcohol is used in manometer, because
• Its vapour pressure is low
• It provides suitable meniscus for the inclined tube
• Its density is less
• It provides longer length for a given pressure difference
Q14 | When a tank containing liquid moves with an acceleration in the horizontal direction, then the free surface of the liquid
• Remains horizontal
• Becomes curved
• Falls on the front end
• Falls on the back end
Q15 | A pressure of 25 m of head of water is equal to
• 25 kN/ m²
• 245 kN/ m²
• 2500 kN/m²
• 2.5 kN/ m²
Q16 | The hammer blow in pipes occurs when
• There is excessive leakage in the pipe
• The pipe bursts under high pressure of fluid
• The flow of fluid through the pipe is suddenly brought to rest by closing of the valve
• The flow of fluid through the pipe is gradually brought to rest by closing of the valve
Q17 | The resultant upward pressure of the fluid on an immersed body is called
• Up-thrust
• Buoyancy
• Center of pressure
• All the above are correct
Q18 | When the water level on the downstream side of a weir is above the top surface of a weir, the weir is known as
• Narrow-crested weir
• Ogee weir
• Submerged weir
Q19 | If the surface of liquid is convex, men
• Cohesion pressure is negligible
• Cohesion pressure is decreased
• Cohesion pressure is increased
• There is no cohesion pressure
Q20 | The atmospheric pressure with rise in altitude decreases
• Linearly
• First slowly and then steeply
• First steeply and then gradually
• Unpredictable
Q21 | Dynamic viscosity of most of the gases with rise in temperature
• Increases
• Decreases
• Remain unaffected
• Unpredictable
Q22 | According to Bernoulli's equation
• Z + p/w + v²/2g = constant
• Z + p/w - v²/2g = constant
• Z - p/w + v²/2g = constant
• Z - p/w - v²/2g = constant
Q23 | Newton's law of viscosity is a relationship between
• Pressure, velocity and temperature
• Shear stress and rate of shear strain
• Shear stress and velocity
• Rate of shear strain and temperature
Q24 | Differential manometer is used to measure
• Pressure in pipes, channels etc.
• Atmospheric pressure
• Very low pressure
• Difference of pressure between two points
Q25 | Non uniform flow occurs when
• The direction and magnitude of the velocity at all points are identical
• The velocity of successive fluid particles, at any point, is the same at successive periods of time
• Velocity, depth, pressure, etc. change from point to point in the fluid flow.
• The fluid particles move in plane or parallel planes and the streamline patterns are identical in each plane